Water-tight plastic container



Sept. 2, 1969. D. J. ASENBAUER WATERf-TIGHT PLASTIVC yCON'I'AINER 4sheets-sheet "1 Filed June' 1, 1967 ,drraeMQ/s Sept. 2, 1969 D. J.ASENBAUER WATER-TIGHT PLASTIC CONTAINER 4 Sheets-Sheet 2 Filed June l,1967 Sept. 2, 1969 r1.1. ASENBAUER WATER-TIGHT PLASTIC CONTAINER 4Sheets-Sheet 3 Filed June 1, 1967 .e .mf [M J. w M w @MMM Sept 2, w69 D.J. ASENBAUER 3,464,579

WATER-TIGHT PLASTIC CONTAINER Filed June 1, 1967 4 Sheets-Sheet 4 wwwUnited States Patent O 3,464,579 WATER-TIGHT PLASTIC CONTAINER Donald J.Asenbauer, Whittier, Calif., assignor to Shell Oil Company, New York,N.Y., a corporation of Delaware Filed June 1, 1967, Ser. No. 642,903Int. Cl. B65d 7/06, 53/02, 45/06 U.S. Cl. 220-4 8 Claims ABSTRACT OF THEDISCLOSURE A container having upper and lower parts, each of which isintegrally formed of thin-walled plastic material, one of the containerparts having an extremity which is curved through an angle of 180 toform a circumferentially extending male joint, the extremity of theother container part being first turned radially outward to form a shelfand then turned at the outer edge of the shelf to form a projectingflange serving as an extension of the container wall; a rigid metal bandattached to the inner wall of the second container part adjacent theshelf, and extending beyond the shelf in parallel relationship to theprojecting flange; a resilient sealing ring located on the shelf andretained in place by both the flange and the rigid band; latch deviceslocated in circumferentially spaced positions around the container andeach including an upper plate secured to one of the container parts anda lower plate secured to the other container part; and rigid fasteningmeans attached to the rigid band and extending through the associatedcontainer wall and attached to the corresponding latch plates.

The present invention relates to a water-tight plastic container havinga novel construction of the sealing joint between the two portions ofthe container.

Background of invention Practical considerations involved in themanufacture of plastic containers limit both the configurations and themechanical strength characteristics of the end product. In forming atwo-part container in which one part has a circumferential edge actingas a male joint member and the other has a circumferential edge actingas a female joint member, the forming of the male joint member is arelatively straight-forward proposition. Where the parts are being madeby a stretch-forming process it is not conveniently possible to form theentire female joint member from the plastic sheet material.

The present invention provides such a structure in which a rigid band isinserted on the interior of the container part that is to form thefemale joint member. The plastic material itself is then used to providethe bottom and outside walls of the female joint, while the rigid metalband provides the inner wall. Latch devices for securing the two halvesof the container together are mountedon the outer wall surfaces, and afurther significant feature of the invention is that an ingenious andvery effective method is used for supporting the latch devices from therigid metal band rather than merely from the plastic parts themselves.

Drawing summary Reference is now made to the drawings illustrating thepresently preferred embodiment of the invention, wherein:

FIGURE l is a perspective view of the container in assembled conditionwith the latches closed;

FIGURE 2 is a top view of the container of FIGURE 1, with a portion ofthe lid structure being shown in crosssection;

FIGURE 3 is a side elevational view of the container,

3,464,579 Patented Sept. 2, 1969 ice with portions being broken away incross-section to illustrate internal features of construction;

FIGURE 4 is a fragmentary view taken on the line 4-4 of FIGURE 3;

FIGURE 5 is a fragmentary cross-sectional view taken on the line 5-5 ofFIGURE 2;

FIGURE 6 is an elevational cross-sectional view taken on the line 6 6 ofFIGURE 3;

FIGURE 7 is a fragmentary view of an interior Wall portion of thecontainer taken on the line 7-7 of FIG- URE 6;

FIGURE 8 is an enlarged fragmentary cross-sectional view of the jointconstruction, taken on the line 8-8 of FIGURE 3;

FIGURE 9 is like FIGURE 8 but shows the latch in a partially openposition;

FIGURE 10 is a perspective view of an upper latch plate;

FIGURE l1 is a perspective view of a lower latch plate;

FIGURE 12 is a fragmentary perspective view of the sealing ring.

Preferred embodiment Reference is now made to the drawings for adescription of the presently preferred embodiment of the invention.Identical containers C (FIGURES 1 and 3) are adapted to be stacked ontop of each other in conventional fashion, with proper alignment beingassured by the interengagement of lugs 28 on the top of one containerwith lugs 18 on the bottom of the superimposed container. Each containerincludes a lower part or box member 10 which has a bottom wall 11 and agenerally perpendicular side wall 12. It also includes an upper part orlid member 20 having a top wall 21 and downwardly depending side wall22. A male joint portion 13- is formed on the upper circumferential edgeof the box member 10, as will subsequently be described; and a femalejoint is formed on the lower circumferential edge 23 of the lid member20. A plurality of latch devices 45 are circumferentially spaced atseparated locations around the container, for securing the upper andlower parts of the container together.

The structure of the male joint will now be described in detail. Sidewall 12 of a second wall member or box member 10 is substantiallyvertical but somewhat outwardly flared. At its upper extremity the malejoint portion 13 is formed, which consists of a 180 outward turn 4in thewall, the wall then extending vertically downward at the outercircumferential edge of the joint. Beyond the male joint 13 anadditional flange 16 is provided, which extends outwardly and downwardlyat an angle of about 45 relative to the side wall 12 and also at anangle of about 45 relative to the horizontal. The flange 16 is a usefulpart of the container as a whole but is not an essential part of themale joint itself.

The female joint is formed in part by the first wall or lid member 20and in part by a rigid metal band 35. The construction of the lid member20 will first be described. At the lower extremity 23 of the side wall22 the wall is turned outwardly to form a horizontally outwardlyextending shelf 24. The shelf 24 has a considerable width, several timesthe thickness of side wall 22. At the radially outward edge of shelf 24the wall is turned downward to form a downwardly projecting flange 25which is essentially an extension of the wall 22. At the downwardextremity of flange 25 the Wall is curved and turned outwardly for ashort distance forming an additional flange 26. The additional flange 26is not an essential part of the female joint, but is, however, a usefulpart of the container as a whole.

The rigid metal band 35 is a single flat piece which extendscircumferentially around the entire interior surface of the wall 22, theends of the band 35 being butt- Welded together at a location not shown.The thickness of band 35 is somewhat less than the thickness of wall 22,and its width is about three times as great as the vertical projectionof flange 25. The upper portion of the rigid band 35 is secured to theinterior surface of wall 22 in such a position that the lower portion ofband 35 ex tends below the shelf 24 in parallel relationship with theflange 25. The lower extremity of band 35 is at about the same elevationas flange 26.

A sponge neoprene sealing strip or ring 30- completes the female jointstructure. Sealing ring 30 is of a substantially rectangularcross-section with its width being approximately equal to the width ofshelf 24, and the thickness of the ring being less than its width.Sealing ring 30 is disposed on the under surface of shelf 24 and istherefore retained in position both by the flange 25 and by the rigidmetal band 35.

The latch devices 45 are circumferentially spaced about the container.Each latch device includes a first or upper metal latch plate 46, asecond or lower metal latch plate 47, and a latch means or clampingmechanism 48. The clamping mechanism 48 is of conventional constructionand need not 'be described in detail. The upper latch plate 46 and thelower latch plate 47 are shown in FIGURES and 11, respectively. Thelatch plates are also of generally conventional construction, but theirshapes are adapted to meet the requirements of this particularcontainer. Specifically, the upper latch plate 46 has an upper shank 46ain which a pair of rivet holes are formed for the purpose of fasteningthe latch plate to the container wall 22, and it also has a lower shank46h which is parallel to the upper shank 46a but displaced outwardlytherefrom by a lateral distance which is equal to the width of shelf 24.A hook 46c is located directly beneath and at the lower end of the shank4611.

The lower latch plate 47 has an upper shank 47a in which a single rivethole is formed, and a lower shank 47b in which a single rivet hole isformed, these two Shanks being aligned so that both will engage the flatouter surface of container wall 12. The central longitudinal portion 47Cof the latch plate 47 is inclined upwardly and outwardly at an angle ofabout 10, as is most clearly seen in FIGURES 8, 9 and 11. The clampingmechanism 48 is fastened to the central latch plate portion 47C, and isadapted for a purely longitudinal pull. Therefore, in the operation ofthe latch as shown in FIGURES 8 and 9, the clamping of the clampmechanism serves to pull the hook 46c in a primarily downward direction,but at the same time inwardly of the container. The effect of this latcharrangement is that the sealing ring 30 is even more narrowly restrictedagainst radially outward flow toward the llange 25 when the latches areclosed, than it would otherwise be. So a very eilective sealing joint isobtained.

An additional feature of great significance is the use of rigidfastening means which join the upper shank 46a of each of the upperlatch plates with the metal band 35. As best seen in FIGURES 8 and 9 apair of rigid fastening means or rivets 40 pass through the openings inlatch plate shank 46a, hence through the plastic wall 22 of the lidmember 20 immediately adjacent the shelf 24, hence through the rigidmetal band 35, and are turned over and secured on the inner surface ofthe metal band. In this manner a rigid support of the metal band 35 isachieved from the latch plate 46, and at the same time, a rigid supportof the latch plate 46 is achieved from the rigid metal band 35. Therigid metal band 35 is therefore firmly secured against radially inwardmovement, and effectively prevents radially inward ow of the sealingring 30 when the container is in its closed condition with the latchesfastened.

An additional feature of some significance is that the outer flanges 26of the lid member and the outer flange 16 of the box member are recessedat each of the various latch locations. This feature of the constructionis clearly seen from FIGURES l, 2, and 8. The advantage of this featureof the construction is that the latches are located within the exterioroutline of the container, and are therefore less subject `to damage orinterference than they would be if in an exposed position.

The container is also provided with a pair of carrying handles 50 on twoof its opposite sides, as shown in FIG- URE l. This feature is notabsolutely essential because the downwardly depending flange 16 of thebox member 10 may be very effectively used as a carrying handle.

In its presently preferred form the container is of a generallyrectangular configuration. The box member 10 is of essentially squareconfiguration in the horizontal plane, and so is the lid member 20. Inits presently preferred application as an instrument case the containermust be secure against breakage for any reason. It is thereforepreferred to provide the lid member 20 with flat truncated corners 27and similarly provided the box member 10 with flat truncated corners 17.The truncated corners increase the strength of the corner structures andminimize the possibility of breakage of the container due to falls orjarring.

An additional special feature of the container is a pressure equalizingvalve 55 which is shown in FIGURE 4. This valve is used in theapplication where the container is used as an instrument case inaircraft, and it is desired to equalize the internal and externalpressure levels.

Alternate forms While the presently illustrated container is ofrectangular configuration it will be readily appreciated that the uniquesealing joint construction may be utilized equally well in a containerthat is of circular, oval-shaped, or other cross-sectionalconfiguration. The rigid band 35 while preferably made of metal may alsobe made of another rigid material such as rigid plastic. Handles 50 arenot essential and may readily be dispensed with. While the presentlyillustrated container utilizes eight of the latches 45, two on each sidewall, four latches would be quite suflicient for most applications. Aparticular configuration of the latch arrangement is illustrated, but itwill be readily appreciated that many other suitable latch arrangementscould be used that would provide satisfactory results.

The invention has been described in considerable detail in order tocomply with the patent laws by providing a full public disclosure of atleast one of its forms. However, such detailed description is notintended in any way to limit the broad features or principles of theinvention, or the scope of patent monopoly to be granted.

Having described the invention, what is claimed as new in support ofLetters Patent is:

1. A fastening and sealing joint for a container having two joiningparts, comprising:

a first thin-walled resilient wall member having an extremity formedinto a generally Z-shaped cross-section so as to provide a substantiallyflat shelf and a flange projecting beyond said shelf;

a fiat rigid metal band disposed in generally parallel relationship tosaid flange and engaging said first wall member on the surface thereofremote from said flange, said shelf, flange, and metal band togetherproviding a generally U-shapped trough;

a plurality of first metal latch plates each having a generally Z-shapedcross-section, being disposed in spaced locations along the length ofSaid flange and each engaging said first wall member on the outer*surface of said llange, beneath said shelf, and on the wall portionimmediately adjacent t-o said shelf;

a plurality of rigid fastening means attached to said metal band andeach extending through said lirst wall member immediately adjacent tosaid shelf and being rigidly fastened to a corresponding one of saidlirst latch plates whereby said metal band and said first latch platestogether provide a rigid supporting structure for said resilient shelfand ilange;

a second wall member having a rounded edge forming a male joint portionadapted to cooperate with said U-shaped trough to provide a joint;

a plurality of second metal latch plates attached to said second wallmember;

and a plurality of latch means each cooperable with a corresponding pairof said latch plates to force said latch plates together and therebymaintain said two wall members substantially in alignment in a commonplane while compressively forcing said male joint portion of said secondwall member into and against said U-shaped trough provided by said firstwall member and said metal band.

2. A joint as claimed in claim 1 wherein said second wall member is madeof thin-walled resilient material and is curved through an angle of 180to provide said male joint portion.

3. A joint as claimed in claim 1 which further includes a resilientsealing strip disposed on said shelf and cornpressed between said malejoint portion and said shelf.

4. A joint as claimed in claim 2 which further includes a resilientsealing strip disposed on said shelf and cornpressed between said malejoint portion and said shelf.

5. A water-tight container as claimed in claim 1 wherein said iirst wallmember forms a hollow box having said U-shaped trough extending aroundthe entire circumferential edge thereof, and said second wall member-forms a hollow lid having said male joint portion extending around itsentire circumferential edge.

6. A water-tight container as claimed in claim 5 wherein said secondwall member is made of thin-walled resilient material and is curvedthrough an angle of to provide said male joint portion.

7. A water-tight container as claimed in claim 5 which further includesa resilient sealing strip disposed on said shelf and compressed betweensaid male joint portion and said shelf.

8. A water-tight container as claimed in claim 6 which further includesa resilient sealing strip disposed on Said shelf and compressed betweensaid male joint portion and said shelf.

References Cited UNITED STATES PATENTS 2,523,760 9/1950 Hayner.

2,916,901 12/ 1959 Claud-Mantle 220-46 X 2,939,603 6/1960 Young 220-43,126,591 3/1964 Hamilton 220-46 3,285,458 11/ 1966 Wojciechowski 220-4FOREIGN PATENTS 1,414,378 9/1965 France. 1,111,946 7/1961 Germany.

GEORGE E. LOWRANCE, Primary Examiner` U.S. Cl. XR,

